1. Field of the Invention
The invention relates to endoscopic suturing, and more particularly to instruments for arthroscopic repair of torn tissue, such as glenoid repair and capsular suture plication.
2. Description of the Related Art
Intracorporeal suturing, particularly suturing tissue during arthroscopic surgery, presents challenges to a surgeon who must manipulate suturing instruments in confined spaces and through a relatively small incision. One device which has been developed for facilitating suturing during arthroscopic surgery is disclosed in U.S. Pat. No. 4,890,615. This instrument has a cannulated or hollow needle secured to a jaw positioned near the end of a long tube. The jaw can be manipulated by a hand grip to press the needle through the tissue to be sutured. Suture material is then fed through the tube from a spool attached to the hand grip into the hollow needle and therefore through the tissue. Enough suture material is advanced through the needle so that when the needle is withdrawn from the tissue and the instrument is removed from the incision, a portion of the suture material remains within the tissue. The suture material is then tied in a manner well-known in the art so as to secure the suture material to the tissue.
While the suture punch of U.S. Pat. No. 4,890,615 generally is effective in suturing tissue, there are several disadvantages associated with using this instrument. For example, the instrument requires manually advancing the suture material through the needle by manipulating the spool, which is often somewhat difficult to do during surgery. In addition, the surgeon must verify that enough suture material has been advanced through the needle so that when the instrument is withdrawn from the incision, the suture material is not inadvertently pulled through the tissue. Furthermore, because the suture material must be fed up and through a hollow needle, tissue or other debris present in the surgical site may block the opening in the needle, making it difficult to pass the suture material through the needle. In addition, because rotating the spool against the braided suture material tended to cause the braided suture material to expand such that it was unable to pass through the tube, only monofilament suture material can generally be used. This is disadvantageous because braided suture material is generally stronger than monofilament suture material. Finally, this particular instrument cannot generally be used to simultaneously pass several segments of suture material through the tissue, which is required for certain types of sutures such as a mattress suture.
The Caspari suture punch, disclosed in U.S. Pat. No. 5,522,820, was developed to provide a suturing instrument for arthroscopic surgery without the above-noted disadvantages. The Caspari suture punch is a hand instrument with a pivotable jaw and a stationary jaw. The stationary jaw is provided with a needle that extends upwardly and has a hook on the proximal side. With the jaws closed, suture is threaded through an aperture in the movable jaw, such that the suture is disposed on the distal side of the needle of the lower jaw and is not engaged by the hook. The instrument is inserted through a relatively small incision in the patient with the jaws closed. With the jaws positioned adjacent the tissue to be sutured, the surgeon opens the jaws (by manipulating the finger grip of the instrument disposed outside the patient), and then closes the jaws to engage the tissue to be sutured. As this occurs, the needle penetrates the tissue to be sutured, and the suture is captured in the hook of the needle. When the movable jaw is then opened, the suture, which is captured in the hook, is drawn through the tissue. The instrument is then removed from the incision and the suture is secured around the tissue with a knot.
While the Caspari punch avoids some of the disadvantages of the prior spool-fed suture punch, it is directed to applications in which the tissue to be sutured must be grasped, and thus requires a movable jaw mechanism. It would be desirable to provide an instrument for suturing which does not require a movable jaw mechanism and is suitable for applications such as rotator cuff repair or surgical plication of a capsule, i.e., capsulorrhaphy.